Pop open a can to toast — the aluminum can – by Tim Philp (Brantford Expositor – September 7, 2017)


We live in a highly engineered world. Virtually everything that we touch has been engineered to be the best it can be for its purpose. Perhaps nothing illustrates this better than the ubiquitous pop can. These marvels of engineering science seem to be such simple devices.

We produce, by one estimate, about 200 billion of such cans every year. That is about 6,700 cans per second. If you placed these cans end to end, you would produce enough to circle the globe in a mere 17 hours. Aluminum cans use about 2.8 billion kilos of aluminum out of a total world production of about 10,680 billion kilograms. So, it is a small — but significant — fraction of the total production.

Aluminum is also one of the most recycled materials on Earth, which is a good thing because aluminum takes a great deal of energy to produce. In terms of energy requirements to mine aluminum, to make four cans requires the equivalent energy of filling one of those cans with gasoline.

It takes about two per cent of the world’s energy to produce the aluminum we use, but producing aluminium from recycled aluminium cans only takes five per cent of the energy needed to produce new aluminium. Even the shape of the can is highly engineered. A pop can starts life as a small disk of aluminum that is pressed through many dies to form its shape. Over time, the aluminum becomes thinner until it is 0.097 millimetres, about as thin as a human hair.

The metal at this point is so fragile that it can be easily crushed by a child, yet the metal is strong enough to hold its contents at about five atmospheres of pressure. Each gram of weight taken from a can represents about 200,000 tonnes of aluminum savings worldwide.

For the rest of this article: http://www.brantfordexpositor.ca/2017/09/07/pop-open-a-can-to-toast—-the-aluminum-can